Method and apparatus for accreting molten material on a moving member



Oct. 23, 1962 J. A. RUSSELL ETAL 3,060,054

METHOD AND APPARATUS FOR ACCRETING MOLTEN MATERIAL ON A MOVING MEMBER Filed Sept. 12, 1960 2 Sheets-Sheet 1 fn ventor-s Jase 015 H. Passe George Gar/son w a 7/2e/r- Attorney Oct. 23, 1962 J. A. RUSSELL ETAL 3,060,054

METHOD AND APPARATUS FOR ACCRETING MOLTEN MATERIAL ON A MOVING MEMBER 2 Sheets-Sheet 2 Filed Sept. 12, 1960 I I I in a T5 n tDM MW fi V e .fl h r ,r f l u, b

United States Patent f 3,060,054 METHOD AND APPARATUS FUR ACCRETDIG MOLTEN MATEREAL ON A MUVING MEMBER Joseph A. Russell, Philadelphia, Pa, and George (Iarb son, Trumbull, Conn, assiguors to General Electric Company, a corporation of New York Filed Sept. 12, 1960, Ser. No. 55,470 15 Claims. (Cl. 11751) This invention relates to a method and apparatus for accreting molten material on a moving member, and more particularly, to a method and apparatus wherein a member of substantially uniform composition may be continuously produced by accretion.

A large portion of the cost of manufacturing stock materials such as rod, tube, and sheet is incurred in the manufacture of primary and intermediate forms of the material from which the stock material is ultimately manufactured. For example, in the manufacture of wire stock from materials such as copper, special equipment such as melting furnaces, large casting apparatus, reheating furnaces, rolling equipment, pickling apparatus, etc., are utilized to produce intermediate wire rod stock which is drawn into wire or other shapes of appropriate size by means of conventional wire apparatus.

An apparatus and a method for continuously depositing by accretion, molten material upon an elongated body having a first cross-sectional configuration of a material having substantially the same composition as the molten material whereby there is formed an elongated body having a second cross-sectional area greater than the first, are disclosed in and said apparatus is claimed in US. Patent No. 3,008,201, which issued from copending application of Roland P. Carreker, Ir., Serial No. 530,283, filed August 24, 1955. pending application of Roland P. Carreker, Jr., Serial No. 98,087, filed March 24, 1961, as a continuation-in-part of said application Serial No. 530,283. This general method is further disclosed and claimed in a more specific and particular form in copending application Serial No. 55,469, filed September 12, 1960, in the names of Roland P. Carreker, Jr., and Robert M. Parke and entitled Method and Apparatus for Accreting Molten Copper on a Moving Member. These applications and this patent were assigned to and are presently owned by the assignee of the present invention. By this means the use of intermediate steps such as, reheating, rolling, pickling, etc., is obviated thereby achieving lower production costs based on lower equipment costs and lower operating costs.

The chief object of the present invention is to provide an improved method and apparatus for accreting molten material on a moving rod to form a rod having greater thickness and being substantially uniform in character.

Another object of the invention is to provide an improved method and apparatus for accreting molten material on a moving rod wherein the rod is cleaned and immediately passed into a vacuum to prevent oxidation of the rod after cleaning to permit accretion in a manner to form a substantially uniform product.

A still further object is to provide a method and apparatus for accreting material on a moving rod wherein the molten rod which is a product of the accretion process passes through a shock isolation loop having improved sensing and driving means associated therewith.

These and other objects of our invention will be more apparent from the following description.

Briefly stated, the present invention relates to a method and apparatus for accreting molten material on a continuously moving rod wherein the rod is passed into an evac uated passage, the entrance of which has associated therewith a cutter which intimately engages the entire periphery of the rod and removes a thin layer of material from The method is claimed in co- $00,054 Patented 0st. 23, 1952' the periphery of the rod to provide a seal and to remove oxidation or other contaminants from the surface of the rod, the rod being introduced into the lower portion of a crucible filled with molten material to permit the molten material to accrete onto the rod, the rod being discharged from the crucible and passed to a shock isolation loop having associated therewith driving means and sensing means for sensing the position of the rod to regulate the speed of the drive means. The term rod as utilized herein designates elongated members of various crosssections being either solid or hollow.

The attached drawings illustrate a preferred embodiment of the invention in which:

FIGURE 1 is a perspective view partially in section of an apparatus for practicing the present invention;

FIGURE 2 is a plan view of means for cleaning the rod and forming the seal to the evacuated passage in the apparatus;

FIGURE 3 is a sectional view of the means shown in FEGURE 2 taken through lines 3-3;

FIGURE 4 is a sectional view of the differential mechanism shown in FIGURE 1; and

FIGURE 5 is a diagrammatic view of another embodiment of the invention.

in FIGURE 1, there is shown a preferred embodiment of the present invention in which core rod 2 is supplied to a drawing apparatus 3 located adjacent a suitable shaving apparatus 4. Core rod 2 supplied to the drawing apparatus may be reduced in cross-sectional area. The

dies of apparatus 3 may also support the core rod as it is introduced to a shaving cutter which removes a thin layer of metal from around the entire periphery of the rod to remove the oxide coating and contaminants therefrom and also to be in such intimate contact therewith so as to form a seal between the shaving cutter and the core rod. The construction and manner of operation of drawing apparatus 3 and shaving apparatus '4 will be more fully described hereinafter.

Core rod 2 after having been cleaned enters into a passage partially defined by tube 5. This passage is evacuated and the condition of the passage is maintained by the previously dscribed seal between the shaving cutter and the rod. The evacuated passage is provided so as to maintain the surface of the rod free from oxidation before the accretion process occurs. The rod passes into idler pulley housing 6 which has located therein a rotatably mounted pulley 7 which changes the direction of rod 2 permitting it to pass into housing 8 wherein is located suitable drive means for urging the rod through the evacuated passage defined by tube 5, housings 6 and 8 and tube 25. This drive means includes pulleys or drive rolls 9 and 10 which are located in the evacuated passage because rod drawing apparatus 3 and rod shaving apparatus 4 require that the rod be pulled therethrough.

Rotative motion is applied to the drive rolls by suitable drive means (not shown) connected to shaft 15 extending from gear reducer 16. One output from gear reducer 16 is shaft 17 which is connected to pulley 10. Pulley 9 is mounted upon shaft 20 and is connected by means of gears 18 and 19 to shaft 17. By this means pulleys 9 and 10 rotate in opposite directions in such a manner as to urge the rod 2 in an upward direction. It will be appreciated that suitable shaft seals may be provided around shafts 17 and 19 to maintain the evacuated condition of the passage.

Gear reducer 16 has a second shaft output 21 connected to gear box 22 having an output 23 which is connected to a second drive means which will be more fully described hereinafter.

In housing 8 there is also located a plurality of pulleys 11 which engage the core rod to perform a supporting and straightening function before the rod is introduced into crucible 26. The rod passes from housing 8 into tube 25 which may have connected thereto a suitable line 27. This line 27 is connected to suitable means such as an evacuating pump to maintain a vacuum in the passage defined by the members 5, 6, 8, and 25. At the upper end of the tube 25 there is located a suitable entrance nozzle, 29 which extends into crucible 26. It can be seen from FIGURE 1 that rod 2 after having been shaved to provide a clean surface thereon is maintained in an evacuated passage and is not permitted to come into contact with an oxidizing atmosphere or other contaminants until after the accretion process has been performed. The clean rod is introduced into nozzle 29 and then into crucible 26 Which has located therein a suitable refractory liner 28 which may be fabricated of graphite. Crucible 26 may be suitably insulated or heated to maintain the temperature of molten material 30, such as copper, located in liner 28. This material may be supplied by a suitable furnace. 31 which may have suitable heating means for melting the copper or other metal to be accreted. If desired, gases, such as oxygen, may be removed from the copper by means of a suitable piece of graphite 34 placed in the melt to unite With the gases permitting the production of copper having a low oxygen content. If desired, the melt in the furnace may also be blanketed with inert gas to reduce oxidation. The molten material, such as copper, is supplied to crucible 26 by means of spout 33 which extends into liner 28 of crucible 26. The level of material 30 in the liner may be sensed by suitable control means 38 which regulates the flow of material from the furnace 31 to maintain a desired level in the crucible and consequently control the time during which accretion of metal takes place upon the cool rod introduced therein. The level of material may be controlled by regulating the level of material in furnace 31. This may be achieved by control means 38 which senses the temperature and liquid level in crucible 26 and which regulates servo motor 37 in response thereto to immerse graphite piece 34. In order to have a smooth surface on the accreted material and also to prevent backflow of molten material into the peripheral area between the rod and nozzle 29, a minimum rod speed must be maintained, the speed varying with the material and rod size. In accreting material on the rod, it is desirable to maintain a nonoxidizing atmosphere above the level of the liquid. This may be achieved by introducing through line 41 an inert gas, such as nitrogen above the level of the melt.

The rod, as it passes through the melt, extracts heat from the molten material. This molten material accretes or solidifies thereon causing the rod to increase in diameter. The rod is discharged from the crucible through nozzle 43. If desired, suitable cooling means, such as water spray nozzles 44, may be utilized to cool the highly heated rod as it leaves the crucible.

The rod emerging from the crucible is in a highly heated state and is extremely fragile. In order to prevent rupture of the rod, 2. suitable shock isolation loop 45 may be provided. This construction changes the direction of the rod through an angle greater than. 90. Shock isolation loop construction 45 comprises a suitable curved arm 46 which pivots about a shaft axis 47. The arm has located thereon a plurality of pulleys 48 which because of counterweight 49 located on an extension of arm 46 causes a controlled tension on the rod to lift it from the crucible. The construction 45 maintains the tension and changes in rod length due to thermal expansion and causes rotation of arm 46 and actuation of a pneumatic valve 50 attached thereto. Valve 50 is connected by means of line 51 to a suitable source of pneumatic pressure and is adapted to control an air motor 52 associated with second drive means for driving the rod from the isolation loop in a manner more fully described hereinafter.

As previously mentioned, the rod emerging from the crucible is of an increased cross-sectional area because of the accretion of metal thereon. This metal is firmly bonded to the rod partially as a result of the clean surface presented when the rod was introduced initially in the crucible. The rod length is substantially increased due to thermal expansion and compensating means must be incorporated in the driving means for removing the rod from the discharge side of the crucible. The previously described arm 46 with its connection to valve 50 comprises a sensing means associated with drive pulleys 55 and 56 located adjacent the shock isolation loop. Power is supplied to the pulleys 55 and 56 through the previously described shaft 23 which is associated with the first drive means including pulleys 9 and 10. Rotation of shaft 23 is transmitted through gear box 60, through sprockets 61 and 62 which are connected by a suitable chain 63. Sprocket 62 is mounted on driving shaft 71 which drives differential mechanism 64 having an output shaft 65 upon which is mounted drive roll 55. Drive roll 56 is driven by shaft 65 through gears 66 and 67. In order to vary the speed of drive rolls 55 and 56, air motor 52 is associated with the differential mechanism 64 through shaft 72. The speed of air motor 52 is controlled by the previously mentioned valve 50 connected to the air motor by means of lines 63 and 69. Valve 52 may be manipulated to cause rotation of shaft 72 in either direction and thus control the speed of pulleys 55 and 56. The nature of this differential mechanism is more fully described hereinafter. A plurality of pulleys positioned adjacent drive rolls 55 and 56 are provided to support the heated rod 2.

Referring to FIGURES 2 and 3, the dies for drawing core rod 2 and the apparatus for shaving the periphery of the rod are mounted upon base 74. Partition 77 extends from base 74 and has mounted thereon a box portion 75 provided to hold a suitable lubricant, such as tallow, through which the rod is passed. After lubrication, rod 2 passes through a die 76 locked in partition 77 by a lock ring 78. Die 76 may perform a combined reducing function and support function. Rod 2 passes through a rotating cutter grooving tool 80, a conventional device which places helical grooves in the rod, and which comprises two blades mounted on a bias in a housing supported by ball bearings 81. Movement of the rod through cutter 80 not only causes deformation or grooving of core rod 2 but also, causes rotation of tool 80 because of the angle of the blades. The grooved rod is passed through partition 79 which with partition 82 forms a second lubricant chamber. The lubricated rod isintroduced into die 83 held in position in die holder 84 by means of lock ring 86. Die holder 84 in turn may be maintained in position in a suitable cavity in partition 82 by means of a plurality of locking bolts 87.

Die 83 is located adjacent a cutter 89 having an annular blade with an undulating edge which functions to remove a thin layer of material including any oxide coating from the rod. The cutting edge simultaneously forms a seal between the rod and the cutter edge. Because of the previous helical grooving operation, the material is removed in the form of chips. Cutter 89 is mounted on housing 90 by means of lock nut 91. Housing 90 has a hollow portion 92 which is sealed from the atmosphere and has located therein a suitable supporting die located adjacent flange 94 of tube 5 described in FIGURE 1. This flange is connected to the housing by means of suitable bolts 95. This flange connection and its associated seals together with cutter 89, tube 5, housings 6 and 8, and tube 25 to nozzle 29 form a passage for the rod. To prevent oxidation of the freshly cleaned rod, this passage is evacuated, this condition being continuously maintained by connecting the passage by means of line 27 to a suitable evacuating pump.

' FIGURE 1 shows a differential mechanism 64 for controlling the speed of drive rolls 55 and 56. FIGURE 4 illustrates a preferred construction for such dilferential mechanism comprising housing into which extends a driving shaft 71 having mounted thereon bevel gear 101. Gear 101 is connected by means of bevel idler gears 103 and 104 to a bevel gear 102 mounted on driven shaft 65 so that rotation of shaft 71 causes rotation of shaft 65. Should idlers 103 and 104 be maintained stationary no speed increase or reduction is achieved. However, since it is desirable to vary the speed of drive rolls 55 and 56, idler gears 103 and 104 are mounted on a carrier 105 journaled in the housing by means of bearings 106. The output speed of shaft 65 may be varied by rotation of the carrier. The carrier is rotated by air motor 52, through shaft connection 72 and bevel gear 109 which is in engagement with bevel gear 108 mounted on the carrier. By this means, air motor 52 controls the rotational speed of drive rolls 55 and 56in response to manipulation of air valve 50.

In the operation of the present invention as embodied in FIGURES 1-4, a continuous core rod is introduced into drawing apparatus 3 wherein the cross-section of the rod is reduced. Before passing through die 76 of drawing apparatus 3, the rod is suitably lubricated. Rod 2 is passed through tool 80 which forms helical grooves thereon. The core rod is again lubricated before passing through die 83 which supports the rod prior to passing through cutter 89 which removes oxide and other contaminants from the surface of the core rod by shaving a thin layer of material from about the periphery of the rod. The intimate contact of the cutter about the periphery of the rod forms a seal between the atmosphere and an opening 92 in housing 90 of the shaving apparatus. Because of the deformed or grooved surface of the rod, the material removed is in the form of chips rather than long shavings. The core rod then passes through die 93 which is provided for support purposes.

The rod passes through tube 5, which is in sealing engagement with shaving apparatus 4 and housing 6, then through housing 6 around pulley 7 and is engaged by drive rolls 9 and 10 in housing 8. These pulleys urge the rod through the housing and also pull the rod through the die and shaving operations previously described. Passing through housing 8 the core rod is supported by pulleys 11 prior to its entry into tube and nozzle 29. It will be appreciated that the surface of the rod is not only clean from oxidation but the entire surface of the rod has also been substantially degassed because of the evacuated environment.

As the core rod enters the crucible liner 28 filled to a predetermined level with molten material 30, it has accreted thereon a layer of molten material which is substantially bonded thereto. The speed of the core rod is such that there is no backflow through nozzle 29 in the space between the rod and the nozzle. The rod emerging from molten material 30 is in substantially a glowing state. An atmosphere of inert gas is maintained above the molten material 30 to prevent oxidation in the crucible. Rod 2 passes through nozzle 43 and is discharged from the crucible. If desired, suitable cooling means 44 may be employed at this point to lower the temperature of the rod.

The rod encounters shock isolation loop 45 which because of the bias of the counterweight 49 urges the pulleys 48 mounted on the arm to engage the high temperature rod whose length has been increased by thermal expansion and Whose cross-sectional area has been increased by accretion. Opposing the bias of counterweight 49 is the driving effect of drive rolls 55 and 56 which attempt to remove the rod as it is discharged from the crucible. Because of the fragile nature of the rod at this point, the driving speed of drive rolls 55 and 56 is varied in response to the force applied to pulleys 48 by the rod in the shock isolation loop. Movement of arm 46 causes rotation of shaft 47 which controls valve 50. Air from valve passes through lines 68 and 69 which varies the speed and direction of rotation of shaft 72 of motor 52.

As previously noted rotational motion transmitted from shaft 15 (FIGURE 1) through shaft 23 through gear box 69 through sprockets 61 and 62 to shaft 71 (shown also in FIGURE 4}. If air motor 52 is not in operation, there is no increase or decrease in the rotational speed of driven shaft 65 over driving shaft 71. Passage of air through either line 63 or 69 determines the direction of rotation of air motor 52. Direction of rotation of output shaft 72 of motor 52 determines the direction of rotation of carrier 195. It can be seen from this construction (FEGURE 4) that rotation of the carrier with idler gears i and 104 mounted thereon will regulate the speed of shaft 65. As can be seen in FIGURE 1 shaft 65 drives drive roll 56 and through gears 66 and 67 drives drive roll 55. The rod is guided through pulleys '70 to a suitable storage area from whence the rod may be periodically removed to drawing means consonant with the ultimate desired product.

FIGURE 5 is a diagrammatic view of another embodiment of the invention wherein the rod is passed into a passage divided into two portions, the first portion containin an inert gas, the second portion being evacuated. in FIGURE 5, rod 2 is passed through shaving device 4' wherein a thin peripheral portion of the rod is removed, the shaving device also serving to seal the atmosphere from the passage starting at tube 5. Inert gas is supplied to tube 5 through line K20. Rod 2 passes through housing 6 around pulley 7, through housing 8' wherein the rod is drivingly engaged by drive rolls 9' and 10. The inert gas in tube 5 and housing 6 and 8' prevents oxidation of the clean rod surface. At the exit from housing 3, a seal which engages the surface of the rod is provided. The portion of the passageincluding tube 25' is evacuated through line 27'. The rod is initially cleaned and immediately passed into an inert gas atmosphere which prevents oxidation of the rod. Prior to being introduced into crucible 26, the rod is passed through an evacuated area which degasses the surface of the rod to permit substantially uniform accretion on the clean rod.

The present invention provides a method and apparatus for accreting material on a continuously moving rod in a manner whereby the cleaning process can be performed at extremely high speeds which do not adversely affect the quality of the cleaning process. This is a major improvement when contrasted with chemical cleaning means wherein a predetermined amount of time in a plurality of cleaning solutions may be required. If a high speed chemical cleaning process is envisioned in order to provide adequate time in cleaning solutions a substantial investment in cleaning equipment is required. The cleaning means provided by the present invention does not have such critical limitations. Also means are provided for handling the rod being discharged from the crucible in a manner wherein the fragile nature of the rod is considered. A shock isolation loop is provided with suitable means for handling the rod and including means for compensating for the increased length of rod due to thermal expansion.

While we have described a preferred embodiment of the invention, it will be understood that the invention is not limited thereto since it may be otherwise embodied Within the scope of the appended claims.

What we claim as new and desire to secure by Letters Patent of the United States is:

1. In an apparatus for accreting molten material on a moving rod, the combination of means defining an evacuated passage, means for passing the rod from the atmosphere into said evacuated passage, a seal member maintaining the condition of the evacuated passage as the rod is introduced into the passage, said seal including means for removing metal from the outer periphery of said rod as it enters the passage whereby the surface of the rod is cleaned, drive means to engage said rod located in said evacuated chamber for driving the rod through the seal member, a crucible, means for maintaining a desired level of molten material in said crucible, nozzle means located in the lower portion of said crucible adapted to introduce the rod into the crucible, means connecting said nozzle to said evacuated passage, seal means associated with the upper portion of the crucible adapted to permit the rod to pass from said crucible, means adapted to change the direction of the rod as it passes from the crucible in a highly heated state, said change in direction constituting a shock isolation loop, means for sensing the position of the rod in said shock isolation loop, second drive means located adjacent the shock isolation loop engaging said rod, said drive means being regulated by the sensing means whereby the sensing means determines increases in length of the rod having molten material solidified thereon to regulate said last mentioned drive means.

2. In an apparatus for accreting molten material on a moving rod, the combination of cleaning means engaging the surface of the moving rod to remove metal from the outer periphery of the rod, drive means for urging the rod through the cleaning means, a crucible, a nozzle located in the lower portion of the crucible adapted to introduce the moving rod into the crucible, an evacuated passage located adjacent the nozzle, said drive means being located between the cleaning means and the nozzle whereby the cleaned rod is urged from the evacuated passage through the nozzle into the crucible, means for changing the direction of the moving rod discharged from the crucible, said means for changing the direction of the rod defining a shock isolation loop, second drive means located adjacent the shock isolation loop for varying the speed of the rod and sensing means for determining the position of the rod in the shock isolation loop to regulate the speed of the second drive means located adjacent thereto.

3. In an apparatus for accreting molten material on a moving rod, the combination of an evacuated passage, means for passing the rod from the atmosphere into said evacuated passage, a seal member maintaining the condition of the evacuated passage as the rod is introduced into said evacuated passage, said seal including means for removing metal from the outer periphery of said rod as it enters the passage whereby the surface of the rod is cleaned, drive means to engage said rod located in said evacuated passage for driving the rod through the seal member, a crucible, means for maintaining a desired level of molten material in said crucible, nozzle means located in the lower portion of said crucible adapted to introduce the rod from the evacuated passage into the crucible, said clean rod having molten material accreting thereto to form a rod having greater thickness.

4. In an apparatus for accreting molten material on a moving rod, the combination of means for cleaning foreign matter from the surface of the rod, a crucible, a nozzle located in the lower portion of the crucible adapted to introduce the rod into the crucible, an evacuated passage located adjacent the nozzle, drive means located between the cleaning means and the nozzle whereby the cleaned rod is urged from the evacuated passage through the nozzle into the crucible wherein molten material accretes thereon, means for changing the direction of the rod discharged from the crucible, said means for changing the direction of the rod defining a shock isolation loop, second drive means located adjacent the shock isolation loop for varying the speed of the rod, and sensing means for determining the position of the rod in the shock isolation loop to regulate the speed of the second drive means located adjacent thereto.

5. The apparatus according to claim 4 further including a driving connection between the drive means located be tween the evacuated passage and the nozzle and the second drive means located adjacent the shock isolation loop, said driving connection comprising a driving gear, a driven gear, an idler gear connecting the driving gear and the driven gear, said idler gear being mounted on a rotatable carrier, motor means for rotating the carrier, said motor means being controlled by said sensing means.

6. In an apparatus for accreting molten material on a moving rod, the combination of cleaning means for engaging the surface of the moving rod to remove metal from the outer periphery of the rod, means for driving the rod through the cleaning means,- a crucible adapted to contain molten material, a nozzle located in the lower portion of the crucible and arranged to introduce the moving rod into the crucible, an evacuated passage located adjacent the nozzle, whereby the cleaned rod may be moved through the evacuated passage and the nozzle into the crucible to have molten material accrete thereto and form a rod of greater thickness.

7. In an apparatus for accreting molten material on a moving rod, the combination of cleaning means for engaging the surface of a moving rod to remove metal from the outer periphery of the rod, a crucible adapted to contain molten material, a nozzle located in the lower portion of the crucible to introduce the moving rod into the crucible, a passage extending from said cleaning means to said nozzle, said cleaning means providing a seal be tween the passage and the atmosphere, means for providing a non-contaminating environment in the passage whereby the clean rod may "he moved through the passage and the nozzle into the crucible to have molten material accrete thereto and form a rod of greater thickness.

8. The apparatus according to claim 7 in which the means for supplying a non-contaminating environment in the passage includes means for supplying inert gas into a portion of the passage.

9. In a method for accreting molten material on a continuously moving rod the steps which consist in passing the rod from the atmosphere into an evacuated passage, engaging the periphery of the rod as it passes into the evacuated passage to remove metal from about the periphery of the rod thereby creating a seal between the rod and the means defining the passage, engaging the rod in the passage to pull the rod through the seal, introducing the moving rod to a nozzle located in the lower portion of a crucible containing molten material, passing the moving rod through said molten material causing accretion of molten material on the moving rod, passing the rod through an inert gas atmosphere, passing the rod from the crucible, changing the direction of the moving rod to form a shock isolation loop, driving the rod through the shock isolation loop at varying speeds and sensing the position of the rod in the shock isolation loop to regulate the speed of the rod.

10. In a method for accreting molten material on a continuously moving rod the steps which consist of passing the rod into an evacuated passage, removing metal from the entire periphery of the rod as it passes into the evacuated passage and simultaneously creating a seal for the rod at the entrance to the passage, passing the rod through a crucible of molten material to cause accretion of molten material on the moving rod to form a rod having greater thickness.

11. In a method for accreting molten material on a continuously moving rod the steps which consist of passing the rod into an evacuated passage, engaging the periphery of the rod as it passes into the evacuated passage to remove metal from about the entire periphery of the rod thereby creating a seal between the rod and the means defining the passage, engaging the rod in the passage to pull the rod through the seal, passing the rod through a nozzle located in the lower portion of a cruci- =ble containing molten material, passing the moving rod through said molten material causing accretion of molten material on the moving rod to form a rod having greater thickness.

12. In a method for accreting molten material on a continuously moving rod the steps which consist of passing the rod from the atmosphere into an evacuated passage, introducing -the moving rod from the passage into a nozzle located in the lower portion of a crucible containing molten material, passing the moving rod through said molten material causing accretion of molten material on the moving rod, passing the rod from the crucible, changing the direction of the moving rod to form a shock isolation loop, driving the rod through the shock isolation loop at varying speeds and sensing the position of the rod in the shock isolation loop to regulate the speed of the rod.

13. In a method for accreting molten material on a continuously moving rod the steps which consist of passing the rod from the atmosphere into an evacuated passage, engaging the rod in the passage to pull the rod into the evacuated passage, introducing the moving rod from the passage into a nozzle located in the lower portion of a crucible containing molten material, passing the moving rod through said molten material causing accretion of molten material on the moving rod, passing the rod from the crucible, changing the direction of the moving rod to form a shock isolation loop, driving the rod through the shock isolation loop at varying speeds and sensing the position of the rod in the shock isolation loop to regulate the speed of the rod.

14. In a method for accreting molten material on a continuously moving rod the steps which consist in passing a rod into a passage, engaging the periphery of the rod as it passes into the passage to remove metal from the outer periphery of the rod to create a seal between a rod and the means defining the passage, maintaining a noncontaminating environment in the passage, passing the rod through a nozzle located in the lower portion of a crucible containing molten material, passing the moving rod through said molten material causing accretion of molten material on moving rod to form a rod having greater thickness.

15. The method according to claim 14 in which the step of maintaining non-contaminating environment in the passage includes supplying an inert gas intoa portion of the passage.

References Cited in the file of this patent UNITED STATES PATENTS 2,092,284 McCarrol et a1. Sept. 7, 1937 2,491,316 Kirk Dec. 13, 1949 2,543,936 Reynolds Mar. 6, 1951 2,545,576 Godley Mar. 20, 1951 2,947,075 Schneckenburger et al. Aug. 2, 1960 2,959,829 Brennan Nov. 15, 1960 FOREIGN PATENTS 706,113 Great Britain Mar. 24, 1954 

9. IN A METHOD FOR ACCRETING MOLTEN MATERIAL ON A CONTINUOUSLY MOVING ROD THE STEPS WHICH CONSIST IN PASSING THE ROD FROM THE ATMOSPHERE INTO AN EVACUATED PASSAGE, ENGAGING THE PERIPHERY OF THE ROD AS IT PASSES INTO THE EVACUATED PASSAGE TO REMOVE METAL FROM ABOUT THE PRERIPHERY OF THE ROD THEREBY CREATING A SEAL BETWEEN THE ROD AND THE MEANS DEFINING THE PASSAGE, ENGAGING THE ROD IN THE PASSAGE TO PULL THE ROD THROUGH THE SEAL, INTRODUCING THE MOVING ROD TO A NOZZLE LOCATED IN THE LOWER PORTION OF A CRUCIBLE CONTAINING MOLTEN MATERIAL, PASSING THE MOVING ROD THROUGH SAID MOLTEN MATERIAL, PASSING THE MOVING TEN MATERIAL ON THE MOVING ROD, PASSING THE ROD THROUGH AN INERT GAS ATMOSPHERE, PASSING THE ROD FROM THE CRUCIBLE, CHANGING THE DIRECTION OF THE MOVING ROD TO FORM A SHOCK ISOLATION LOOP, DRIVING THE ROD THROUGH THE SHOCK ISOLATION LOOP AT VARYING SOEEDS AND SENSING THE POSITION OF THE ROD IN THE SHOCK ISOLATION LOOP TO REGULATE THE SPEED OF THE ROD. 